U.S. patent number 5,731,800 [Application Number 08/475,833] was granted by the patent office on 1998-03-24 for output method and apparatus.
This patent grant is currently assigned to Canon Kabushiki Kaisha. Invention is credited to Akio Sugaya.
United States Patent |
5,731,800 |
Sugaya |
March 24, 1998 |
Output method and apparatus
Abstract
An output apparatus includes a memory for storing attribute
information and an output resolution of a character pattern, an
outline font forming unit for forming an outline font on the basis
of font information in a dot pattern format, a dot pattern forming
unit for forming a dot pattern font on the basis of the outline
font in accordance with the attribute information and the
resolution, and an output unit for displaying and outputting the
dot pattern formed by the dot pattern forming unit.
Inventors: |
Sugaya; Akio (Yokohama,
JP) |
Assignee: |
Canon Kabushiki Kaisha (Tokyo,
JP)
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Family
ID: |
26553203 |
Appl.
No.: |
08/475,833 |
Filed: |
June 7, 1995 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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125144 |
Sep 23, 1993 |
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778373 |
Oct 17, 1991 |
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Foreign Application Priority Data
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Oct 19, 1990 [JP] |
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2-279180 |
Oct 19, 1990 [JP] |
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2-279181 |
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Current U.S.
Class: |
345/471;
358/1.11 |
Current CPC
Class: |
G06K
15/02 (20130101); G06K 2215/0045 (20130101); G06K
2215/0057 (20130101); G06K 2215/0034 (20130101) |
Current International
Class: |
G06K
15/02 (20060101); G06K 001/00 () |
Field of
Search: |
;345/141,142,143,144,192,193,194,195 ;340/731,735 ;400/121
;395/110,102 ;382/301 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1-191192 |
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Aug 1989 |
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JP |
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1-290448 |
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Nov 1989 |
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JP |
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2-63855 |
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Mar 1990 |
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JP |
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2-202461 |
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Aug 1990 |
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JP |
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Primary Examiner: Saras; Steven
Attorney, Agent or Firm: Fitzpatrick, Cella, Harper &
Scinto
Parent Case Text
This application is a continuation of application Ser. No.
08/125,144 filed Sep. 23, 1993, now abandoned, which was a
continuation of application Ser. No. 07/778,373 filed Oct. 17,
1991, now abandoned.
Claims
What is claimed is:
1. An output apparatus comprising:
first storage means for storing character font information as a dot
pattern;
outline generating means for generating an outline font on the
basis of the stored dot pattern;
outline font storage means for storing the outline font generated
by said outline generating means;
dot pattern generating means for generating a character dot pattern
having a size corresponding to form information;
second storage means for storing the generated character dot
pattern formed by said dot pattern generating means;
third storage means for storing information representing a
plurality of resolutions available in said output apparatus;
and
output means for outputting, in the case that the dot pattern
stored in the first storage means does not have the size
corresponding to the form information, the generated character dot
pattern stored in said second storage means, having the size
corresponding to the form information, and having one of the
plurality of resolutions represented by the information stored in
said third storage means.
2. An apparatus according to claim 1, further comprising means for
visualizing the dot pattern output by said output means.
3. An apparatus according to claim 2, wherein said visualizing
means comprises a printer.
4. An output method comprising the steps:
generating outline data on the basis of a first dot pattern;
generating a second dot pattern having a corresponding size of the
outline data in accordance with form information and an output
resolution; and
outputting the second dot pattern if the first dot pattern does not
correspond to a dot pattern to be output having the output
resolution.
5. An output apparatus comprising:
storage means for storing character information, an output size,
and an output resolution of the character information;
scalable font generating means for generating a scalable font on
the basis of dot pattern font information;
dot pattern generating means for generating a dot pattern on the
basis of the generated scalable font and the character information,
the output size, and the output resolution stored in said storage
means; and
output means for outputting the dot pattern after said dot pattern
has been generated by said dot pattern generating means,
wherein the dot pattern generated by said dot pattern generating
means is different in size from the dot pattern font
information.
6. An apparatus according to claim 5, further comprising means for
visualizing the dot pattern output by said output means.
7. An apparatus according to claim 6, wherein said visualizing
means comprises a printer.
8. An information processing system comprising:
a computer which outputs character information; and
an output apparatus comprising:
first storage means for storing character font information as a dot
pattern in correspondence to the character information output by
said computer;
outline generation means for generating an outline font on the
basis of the stored dot pattern;
outline font storage means for storing the generated outline font
generated by said outline generating means;
dot pattern generating means for generating a character dot pattern
having a size corresponding to form information;
second storage means for storing the generated character dot
pattern formed by said dot pattern generating means;
third storage means for storing information representing a
plurality of resolutions available in said output apparatus;
and
output means for outputting, in the case that the dot pattern
stored in said first storage means does not have a size
corresponding to the form information, the generated character dot
pattern stored in said second storage means, having the size
corresponding to the form information, and having one of the
plurality of resolutions represented by the information stored in
said third storage means.
9. An output method carried out in an output apparatus having a
first memory for storing character font information as a dot
pattern and a second memory for storing information representing a
plurality of resolutions available in the output apparatus, said
method comprising the steps of:
generating an outline font on the basis of the dot pattern stored
in the first memory;
storing the generated outline font in a third memory;
generating a character dot pattern having a size corresponding to
form information;
storing the generated character dot pattern in a fourth memory;
and
in a case that the dot pattern stored in the first memory does not
have the size corresponding to the form information, outputting the
generated character dot pattern stored in the fourth memory, having
the size corresponding to the form information, and having one of
the plurality of resolutions represented by the information stored
in the second memory.
10. A computer-readable memory medium storing computer-executable
process steps carried out in an output apparatus having a first
memory for storing character font information as a dot pattern and
a second memory for storing information representing a plurality of
resolutions available in the output apparatus, the steps
comprising:
a generating step to generate an outline font on the basis of the
dot pattern stored in the first memory;
a storing step to store the generated outline font in a third
memory;
a generating step to generate a character dot pattern having a size
corresponding to form information;
a storing step to store the generated character dot pattern in a
fourth memory; and
in a case that the dot pattern stored in the first memory does not
have the size corresponding to the form information, an outputting
step to output the generated character dot pattern stored in the
fourth memory, having the size corresponding to the form
information, and having one of the plurality of resolutions
represented by the information stored in the second memory.
Description
BACKGROUND OF THE INVENTION
1. Field of the invention
The present invention relates to a character pattern output
apparatus, which can register an outline font obtained by
converting dot pattern information, and can display and output a
dot pattern obtained by converting the outline font.
2. Related Background Art
In, e.g., a printer for receiving character codes, and printing
characters on, e.g., a recording sheet, character pattern
information is stored in a font memory in a dot pattern format or
an outline format. Upon reception of a character code,
corresponding pattern data or outline font is read out from the
font memory, and is developed to a dot pattern to perform
recording. The pattern development based on the outline font is
advantageous since characters can be easily enlarged or reduced. In
general, however, font information using a dot pattern is still
popular.
When a printer which stores font information in the dot pattern
format performs a recording operation while changing a resolution,
if a printing operation is performed using character fonts stored
in the dot pattern format, characters having different sizes are
undesirably printed in accordance with resolutions. For example,
when a printing operation is performed at a resolution of 180 dpi
(dots/inch), the print size of a character dot pattern constituted
by a 25.times.25 dot matrix is about 10 points (1 point=1/72 inch).
However, when this character is printed at a resolution of 360 dpi,
the printed character size undesirably becomes about 5 points.
For this reason, in order to print characters having the same size
at different resolutions, in, e.g., the above-mentioned case, every
time a character is received, an outline font must be temporarily
formed based on the 25.times.25 dot font, and a dot pattern (50
dots.times.50 dots) must be generated and printed, so that when the
formed outline font is printed at a dot density of 360 dpi, the
printed character has a size of 10 points.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide an output
method and apparatus, which can register an outline font formed
based on a dot pattern, and can display and output a dot pattern
having a size suitable for a character attribute.
It is another object of the present invention to provide a
character pattern output apparatus comprising input means for
inputting attribute information of a character, memory means for
storing a resolution of a character pattern display output unit,
outline font generation means for generating an outline font on the
basis of font information in a dot pattern format, storage means
for storing the outline font, dot pattern generation means for
generating a dot pattern font based on the outline font in
accordance with the attribute information and the resolution, and
output means for displaying and outputting the pattern generated by
the dot pattern generation means.
It is still another object of the present invention to provide an
output method and apparatus, which generate an outline font based
on font information in a dot pattern format, store the outline
font, generate a dot pattern font based on the stored outline font
in accordance with attribute data of a corresponding character and
a resolution of a display output unit, and display and output the
generated pattern.
It is still another object of the present invention to provide an
output method and apparatus, which can generate an outline font
based on a dot pattern, and can register a dot pattern which is
formed to have a size according to a resolution of a recording
unit, so that a high-speed output operation can be assured even
when the resolution is changed.
It is still another object of the present invention to provide an
output apparatus comprising input means for inputting form
information of a document, recording means which receives image
data formed by a dot pattern, and can record the image data while
changing a resolution, first storage means for storing font
information of a character as a dot pattern, outline font
generation means for generating an outline font based on the dot
pattern, outline font storage means for storing the outline font,
dot pattern generation means for generating a character dot pattern
having a size corresponding to the form information, and a
recordable resolution of the recording means on the basis of the
outline font, second storage means for storing the dot pattern
generated by the dot pattern generation means, and pattern
development means for reading out the dot pattern having a size
corresponding to the form information and the resolution from one
of the first and second storage means, and performing pattern
development of the readout pattern to form image data.
It is still another object of the present invention to provide an
output method and apparatus which store character font information
as a dot pattern, generate and store an outline font based on the
dot pattern, and generate and store a character dot pattern having
a size corresponding to form information and a recordable
resolution of recording means on the basis of the outline font,
whereby a corresponding dot pattern is read out and printed in
correspondence with designated form information and a
resolution.
It is still another object of the present invention to provide an
output method and apparatus, which can give a resolution
non-dependency to an externally input down-load font.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic block diagram showing an arrangement of a
control unit for an LBP according to an embodiment of the present
invention;
FIG. 2 is a view showing tables which relate font information in
the LBP of this embodiment with a character code;
FIG. 3 is a flow chart showing character pattern registration
processing in the LBP of this embodiment;
FIG. 4 is a flow chart showing printing processing in the LBP of
this embodiment;
FIG. 5 is a flow chart showing printing processing in an LBP
according to another embodiment of the present invention;
FIG. 6 is a sectional view showing a structure of a printer engine
of the LBP of this embodiment;
FIG. 7 is a block diagram showing an arrangement of a control unit
for an LBP according to still another embodiment of the present
invention;
FIG. 8 is a view showing the relationship between a dot pattern
table and an outline font table;
FIG. 9 is a flow chart showing character pattern registration
processing in the LBP according to the embodiment shown in FIG. 7;
and
FIG. 10 is a flow chart showing printing processing in the LBP
according to the embodiment shown in FIG. 7.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiment of the present invention will be described
in detail below with reference to the accompanying drawings.
<Printer (FIG. 6)>
FIG. 6 is a sectional view showing an internal structure of a laser
beam printer (to be abbreviated to as an LBP hereinafter) according
to this embodiment. Note that this LBP can register a character
pattern (dot pattern data) received from a data source (not shown),
and can also register a standard form (form data).
In FIG. 6, an LBP main body 600 can receive and store character
information (character code), form information, or a macro command
from, e.g., an external host computer, and can form a character
pattern or a form pattern according to these pieces of information
so as to form an image on a recording sheet as a recording medium.
A printer control unit 601 controls the overall LBP 600, and
analyzes, e.g., character information supplied from the host
computer. The control unit 601 mainly converts character
information into a video signal of a corresponding character
pattern, and outputs the converted signal to a laser driver 602. An
operation panel 612 includes operation switches, LED indicators,
and the like.
The laser driver 602 drives a semiconductor laser 603, and turns
on/off a laser beam 604 emitted from the semiconductor laser 603 in
accordance with an input video signal. The laser beam 604 is
deflected by a rotary polygonal mirror 605 in the right-and-left
direction in FIG. 6, thus scanning the surface of an electrostatic
drum 606. As a result, an electrostatic latent image of a character
pattern is formed on the electrostatic drum 606. The electrostatic
latent image is developed by a developing unit 607 arranged around
the electrostatic drum 606, and is then transferred onto a
recording sheet.
As the recording sheet, cut sheets are used. The cut recording
sheets are stored in a paper cassette 608 attached to the LBP 600.
Each recording sheet is fetched into the apparatus by a paper feed
roller 609 and convey rollers 610 and 611, and is fed to the
electrostatic drum 606. The recording sheet on which an image is
transferred and recorded by the electrostatic drum 606 is exhausted
onto a tray 615 by recording sheet exhaust rollers 613 and 614.
A printer engine unit shown in FIG. 6 can change the resolution,
and can perform a printing operation at a plurality of
resolutions.
<Control Unit 601 (FIG. 1)>
FIG. 1 is a block diagram of the control unit 601 for controlling
the overall LBP 600.
In FIG. 1, a host computer 100 outputs various data to the LBP 600.
A receiving buffer 101 stores data received from the host computer
100. A CPU 102 controls the overall LBP 600, and executes various
control operations in accordance with a control program stored in a
ROM 102a. A RAM 102b is used as a work area for the CPU 102, and
temporarily stores various data.
A registration memory 103 stores an outline font generated based on
a registered dot pattern. A page buffer 104 stores data received
from the host computer 100 in units of pages. A bit map memory 105
stores an output image for one page to be output to a printer
engine 106. The printer engine 106 prints image data stored in the
bit map memory 105 on a recording sheet 107. The recording sheet
107 is printed in this manner. A resolution memory 108 stores the
current printing resolution of the printer engine 106.
With the above arrangement, when a dot pattern font is input from
the host computer 100, it is temporarily converted into an outline
font, and the converted outline font is stored in the registration
memory 103.
A case will be explained below wherein a character code is input
from the host computer 100, a character size, a form, a printing
resolution, and the like are instructed, and start of printing is
then instructed. In this case, an outline font registered in the
registration memory 103 is read out, and is converted into a dot
pattern to have a size corresponding to attribute information such
as the resolution, form, and the like. The converted dot pattern is
developed onto the bit map memory 105 as a bit map image. In this
manner, even when various character sizes are designated, a
printing operation can be performed with suitable character
sizes.
<Management of Outline Font (FIG. 2)>
FIG. 2 is a view for explaining management of an outline font
generated based on a dot pattern font.
In FIG. 2, a character set management table 201 is used for
managing an outline font registered in the registration memory 103.
A pointer table 202 indicates a registered character set, and
manages all the character sets which can be used in this printer.
An attribute storage 203 stores an attribute (Ming type, Gothic
type, or the like) of a character set indicated by the pointer
table 202, and is used when an outline font is selected, and is
pattern-developed.
A registered character set information portion 204 is indicated by
the pointer table 202. In the information portion 204, the width,
height, attribute, and the like of the character set are described.
Character pointers 205 are stored in the character set information
portion 204, and respectively store the start addresses of outline
fonts (e.g., 206 and 207) registered in the registration memory 103
in correspondence with character codes.
<Character Pattern Registration Processing (FIG. 3)>
FIG. 3 is a flow chart showing a character pattern registration
processing sequence in the LBP 600 of this embodiment. A control
program for executing this processing is stored in the ROM 102a.
Prior to this processing, registered data of character patterns are
already transferred from the host computer 100, and are stored in
the receiving buffer 101.
In step S1, character set information for storing a character type,
a type face, and the like (FIG. 2) is generated, and its address is
stored in the pointer table 202 of the character set management
table 201. Furthermore, attribute information such as a character
width, a character height, a type face, and the like is stored in
the attribute storage 203.
In step S2, the character set information portion 204 is generated,
and its address is stored in the pointer table 202 in the character
set management table 201. As described above, an outline font
registered as will be described later, the character set
information portion 204, and the character set management table 201
are related to each other.
In step S3, a dot pattern for one character is read out from the
receiving buffer 101. In step S4, outline extraction processing of
the dot pattern is executed to extract an outline of a character,
thereby generating an outline font.
Thereafter, the flow advances to step S5, and the start address of
the outline font stored in the registration memory 103 is stored in
the character pointer 205 of the character set information portion
204 in correspondence with a character code. The above-mentioned
processing is repeated until registration of all the character
patterns sent from the host computer 100 is completed in step
S6.
In this manner, the outline fonts generated based on the dot
patterns sent from the host computer 100 are registered in the
registration memory 103. The start addresses of the outline fonts
in the registration memory 103 are stored in the tables 201 and 204
in association with character codes corresponding to the fonts
together with pieces of attribute information.
<Printing Processing (FIG. 4)>
FIG. 4 is a flow chart showing a processing sequence for printing
registered character patterns by the LBP 600. This control program
is stored in the ROM 102a.
In step S11 in FIG. 4, character set information (Ming type, Gothic
type, or the like) for selecting characters, and a character form
(height and width) are input from the host computer 100. In step
S12, a corresponding character set is selected from the character
set management table 201 using the character set information input
in step S11. In this case, information such as a character height,
a character width, and the like in the character set information
selected from the character set management table 201 can be
different from values input in step S11. Since the outline fonts
are registered, they can be converted into dot patterns in
correspondence with the attribute information.
The flow then advances to step S13, and a character code received
from the host computer 100 is read out from the receiving buffer
101. In step S14, the character pointer, corresponding to the
readout character code, of the selected character set information
portion 204 is looked up, thereby extracting a corresponding
outline pattern font from the registration memory 103.
The flow advances to step S15, and the readout outline font is
developed to a dot pattern in accordance with the character form
input in step S11, and the printing resolution of the printer
engine 106 stored in the resolution memory 108, thus obtaining a
desired dot pattern.
The dot pattern obtained in this manner is stored in the bit map
memory 105 in step S16. The above-mentioned processing is repeated
until bit map data for one page are developed on the memory 105.
Upon completion of image data for one page, the flow advances to
step S18, and the image data is output to 10 the printer engine 106
shown in FIG. 6, thus printing an image on the recording sheet.
<Another Embodiment (FIG. 5)>
FIG. 5 is a flow chart showing printing processing by an LBP
according to another embodiment of the present invention.
In step S21 in FIG. 5, character set information (Ming type, Gothic
type, or the like) for selecting characters, and a character form
(height and width) are input from the host computer 100. In step
S22, dot pattern fonts stored in the ROM 102a originally
incorporated in the printer are selected from the character set
management table 201 on the basis of the input character set
information. In this case, the character height and width of the
character set information designated in step S21 may be different
from those of attribute information stored in the management table
201. As will be described later, the dot pattern font is
temporarily converted into an outline font, and thereafter, the
outline font is developed to bit map data.
In step S23, as shown in FIG. 2, a character set information
portion which stores a character type, a type face, and the like of
the dot font is formed, and its address is stored in the pointer
table 202 of the character set management table 201. In addition,
attribute information such as a character width, a character
height, a type face, and the like is stored in the attribute
information storage 203. In step S23, the area of the character
information portion 204 is assured, and its address is stored in
the pointer table 202 of the character set management table 201. In
this manner, the address of an outline font which is to be formed
based on the dot pattern, and is to be registered in the
registration memory 103 can be looked up from the character set
management table 201.
In step S24, a dot pattern for one character is read out from the
dot pattern fonts selected in step S22, and outline extraction
processing of the pattern is executed to extract an outline of a
character. Then, an outline font is generated on the basis of the
outline information. The outline font formed in this manner is
stored at the address of the registration memory 103 indicated by
the character pointer 205 in the character set information portion
204 in step S25. This processing is repetitively executed until
conversion of all the dot patterns to outline fonts, and
registration of the outline fonts are completed in step S26.
After the outline fonts are formed and registered in this manner,
the character code sent from the host computer 100 is read out from
the receiving buffer 101 in step S27. In step S28, the character
pointer, corresponding to the character code, of the character set
information portion 204 selected in step S22 is looked up, thereby
reading out the outline pattern font from the registration memory
103.
In step S29, the outline font is developed to a dot pattern in
accordance with the character form input in step S21, and the
resolution of the printer engine 106 (the content of the resolution
memory 108), thus obtaining a desired dot pattern. The dot pattern
obtained in this manner is written in the bit map memory 105 in
step S30, thus generating image information of a character pattern.
The above-mentioned processing is repeated until image data for one
page are formed on the bit map memory 105 in step S31. When the
image data for one page are formed on the bit map memory 105, the
flow advances to step S32, and an image is recorded on a recording
sheet by the printer engine 106 shown in FIG. 6.
As described above, according to this embodiment, when dot patterns
are down-loaded, they can be converted in advance to outline fonts,
and the outline fonts are registered. Thus, processing for
converting a dot pattern into an outline font every time one
character is received and printed can be omitted. Therefore, a time
required for printing desired character patterns can be
shortened.
In this embodiment, the printer has been exemplified as the
character pattern output apparatus. However, the present invention
is not limited to this, but may be applied to a display apparatus
such as a CRT display.
As described above, according to the present invention, since
outline fonts are formed based on dot patterns, and are registered,
dot patterns having a size suitable for a character attribute can
be displayed and output.
Still another embodiment will be described below. The same
reference numerals in this embodiment denote the same parts as in
FIG. 1, and a detailed description thereof will be omitted.
In FIG. 7, a registration memory 103 stores dot pattern fonts. A
font memory 104 stores outline fonts generated based on the dot
pattern fonts stored in the registration memory 103, and dot fonts
generated based on the outline fonts. A page buffer 105 stores data
received from a host computer 100 in units of pages. A bit map
memory 106 stores an output image for one page to be output to a
printer engine 107. The printer engine 107 has an arrangement shown
in detail in FIG. 6, and prints image data stored in the bit map
memory 106 on a recording sheet 108. The recording sheet 108 is
printed in this manner. A resolution memory 109 stores a current
recording resolution of the printer engine 107.
With the above arrangement, when a dot pattern font is input from
the host computer 100, it is registered in the registration memory
103, and is temporarily converted into an outline font. The
converted outline font is then converted into a dot pattern
according to another printing resolution of the printer engine 107,
and the converted dot pattern is stored in the font memory 104.
For example, when the printer engine 107 can perform printing
operations at 180 dpi and 360 dpi, if a character dot pattern which
has a character size of 10 points (25 dots.times.25 dots) at 180
dpi is input, the dot pattern is temporarily converted into an
outline font. Furthermore, a character dot pattern is formed using
the outline font, so that the dot pattern can have a character size
of 10 points (50 dots.times.50 dots) when it is printed at 360
dpi.
A case will be explained below wherein a character code is input
from the host computer 100, a character size, a form, a printing
resolution, and the like are instructed, and start of printing is
then instructed. In this case, when a printing operation can be
performed with the designated character size using dot patterns (10
points at 180 dpi, 25 dots.times.25 dots) registered in the
registration memory 103, the input dot patterns are directly used,
and are pattern-developed onto the page buffer 105.
On the other hand, when the resolution of the printer engine 107
is, e.g., 360 dpi, and the size of characters printed using the dot
patterns in the registration memory 103 is different from the
designated size (10 points), the dot patterns, which are already
developed to 50 dots.times.50 dots using the outline fonts, are
developed into bit map data.
Furthermore, when there are no dot patterns with which characters
having the same size as the designated size (10 points) can be
printed in correspondence with the resolution of the printer engine
107, an outline font stored in the font memory 104 and
corresponding to the input character code is read out, and is
converted into a dot pattern having a corresponding size. The dot
pattern is developed into bit map data on the page buffer 105. In
this manner, even when various character sizes and resolutions are
designated, a printing operation can be performed with the suitable
character size.
This operation will be described in detail below.
<Management of Font Data (FIG. 8)>
FIG. 8 shows an architecture of a management table for managing dot
pattern fonts, and outline fonts formed based on the dot pattern
fonts. This table is stored in a RAM 102b.
In FIG. 8, a dot font management table 201 manages all the dot
pattern fonts including dot fonts which serve as original patterns
upon formation of outline fonts. An outline font management table
202 manages only outline fonts formed based on the dot pattern
fonts.
A dot font information portion 203 stores dot font information
registered in the registration memory 103, and character pointers
206 for indicating character patterns corresponding to character
codes. A dot pattern font 209 is one registered in the registration
memory 103. For example, a dot pattern 209a is designated when the
index of the dot font management table 201 is "0" (25 dots.times.25
dots), and the pointer (character code) of the font information
portion 203 is "0", and a dot pattern 209b is designated when the
pointer of the dot font information portion 203 is "1".
More specifically, for example, index "0" is used when received dot
patterns (e.g., having a character size of 10 points at 180 dpi)
are directly stored, and index "1" indicates dot patterns which can
be printed to have the same size (10 points) as that of characters
printed using the dot patterns of index "0" when the resolution of
the printer engine 107 is 360 dpi.
A dot font information portion 205 has a different character size,
and manages dot patterns stored in the font memory 104 and formed
based on an outline font. This information portion 205 stores
character pointers 208 for designating character patterns in
one-to-one correspondence with character codes. A dot pattern font
211 is one stored in the font memory 104, and formed based on an
outline font. In this case, a dot pattern 211a is designated when
the index of the dot font management table 201 is "1" (50
dots.times.50 dots), and the pointer (character code) of the font
information portion 205 is "0" like in the dot pattern font 209
described above, and a dot pattern 211b is designated when the
pointer of the dot font information portion 205 is "1".
An outline font information portion 204 stores information of
outline fonts formed based on the dot pattern fonts in the
registration memory 103, and stored in the font memory 104, and
character pointers 207 for indicating character patterns in
one-to-one correspondence with character codes. An outline font 210
is one stored in the font memory 104. An outline font pattern 210a
is designated when the character pointer is "0", and an outline
font pattern 210b is designated when the character pointer is
"1".
<Registration Sequence (FIG. 9)>
FIG. 9 is a flow chart showing a character pattern registration
processing sequence in an LBP 600 of this embodiment. A control
program for executing this processing is stored in a ROM 102a.
Prior to this processing, dot pattern data to be registered in the
registration memory 103 are transferred from the host computer 100,
and are stored in a receiving buffer 101.
In step S1, an area of a character set information portion (the dot
font information portion 203 in FIG. 8) for storing a character
type, a type face, and the like of a dot font to be registered in
the registration memory is assured, and its address is stored in
the dot font management table 201. Similarly, the area of the
outline font information portion 204 is assured, and its address is
stored in the pointer table in the outline font management table
202. In this case, as shown in FIG. 8, the storage number (pointer
number) of the dot font management table 201 is stored as an index
(character size information) of the outline font management table
202 to the dot font management table. Furthermore, the value of the
pointer of the dot font management table 201 is stored as an index,
so that dot font information corresponding to a different
resolution can be looked up using this table 202.
In this manner, the dot font pattern information portions 203 and
205, and the outline font information portion 204 formed based on
the dot patterns are linked.
The flow then advances to step S2, and a dot pattern for one
character is read out from the receiving buffer 101. In step S3,
the readout pattern is registered in the registration memory 103.
In this case, the start address of the registration memory 103,
where the dot pattern font 209 is stored, is stored in the
character pointer 206 of the dot pattern font information portion
203 in FIG. 8 to link the registration memory with the dot pattern
font information portion, so that character codes can have
one-to-one correspondence with character patterns.
The flow then advances to step S4. In step S4, the dot pattern font
registered in the registration memory 103 is read out, and outline
extraction processing of the dot pattern is executed to extract an
outline point string of a character, thus forming an outline font.
The outline font formed in this manner is stored in the font memory
104 as an outline font in step S5.
In this case, the start address of the font memory 104, where the
outline font is stored, is stored in the character pointer 207 of
the outline font information portion 204 to link the font memory
with the outline font information portion, so that character codes
can have one-to-one correspondence with character patterns.
The flow then advances to step S6, and a dot pattern having a size
(50 dots.times.50 dots in the above-mentioned case) different from
that of the dot patterns registered in the registration memory 103
is formed using the outline font registered in step S5. This is to
print characters to have the same size as the character size
designated by attribute information such as form information even
when the resolution of the printer engine 107 is set to be a
different value, as described above.
In step S7, the address of the font memory 104, where the dot
pattern font formed based on the outline font is stored, is stored
in the character pointer 208 of the dot font information portion
205. In this case, the storage number ("1" in FIG. 8) of the dot
font font management table is set in the index of the outline font
management table 202.
In this manner, the outline font information portion, and the dot
font information portion formed based on the outline font are
related to each other.
The above-mentioned processing is repeated until registration of
all the character patterns stored in the receiving buffer 101 and
development to the outline fonts are completed in step S8.
<Printing Processing (FIG. 10)>
FIG. 10 is a flow chart showing a printing processing sequence for
developing character codes input from the host computer 100 into
pattern data, and printing the pattern data in practice. A control
program for executing this processing is stored in the ROM
102a.
In step S11 in FIG. 10, character set information (Ming type,
Gothic type, or the like) for selecting characters are input from
the host computer 100. The flow advances to step S12 to select an
outline font corresponding to the character code from the outline
font management table 202 using the character set information. In
step S13, a character form (a character height and width) is
designated.
In step S14, the index of the outline font selected in step S12 to
a dot character set, which index is stored in the outline font
management table 202, is read out, and character height information
and width information indicated by the readout index are read out
from the dot font management table 201. It is then checked if the
character size of dot pattern data registered in the table 201 is
the same as the character form designated in step S13.
If the character size of dot pattern data is not the same as the
character form, the flow advances to step S17 to check all the
indices of the dot fonts of the outline font management table 202.
All the indices are checked in step S17, and if a font having the
same size is found, the flow returns to step S15. In step S15, a
character code is read out from the receiving buffer 101, and in
step S16, a dot pattern corresponding to the readout character code
is read out from the font memory 104 or the registration memory
103. The flow then advances to step S20, and the readout dot
pattern is developed onto the bit map memory 106.
On the other hand, if it is determined in step S17 that the
character sizes of registered dot pattern data cannot be printed in
the same character size in consideration of the character form
designated in step S13 and the resolution after all the indices are
read out, the flow advances to step S18, and outline font
information corresponding to the character code is read out from
the font memory 104 in accordance with the character pointer 207
stored in the outline font information portion 204.
The flow then advances to step S19, and the readout outline font
information is developed to form a character dot pattern
corresponding to the character form designated in step S13 and the
printing resolution.
In step S20, the dot pattern obtained in this manner is developed
into bit map data on the bit map memory 106, thereby generating
image information of the character pattern. If bit map data for one
page is formed in step S21, the flow advances to step S22, and an
image is printed on a recording sheet using the printer engine
described above with reference to FIG. 6.
In this manner, according to this embodiment, when a dot pattern
font is registered, an outline font is formed on the basis of the
dot pattern, and a dot pattern having another size according to a
resolution of a recording unit is formed based on the outline font
and is registered in advance. Thus, when a printing operation of
characters having a size other than that of an original dot pattern
size is designated, the printing operation can be performed using
the new dot pattern. Therefore, a printing processing time can be
shortened.
In this embodiment, an outline font is formed based on a dot font
registered by, e.g., the host computer. However, the present
invention is not limited to this. For example, an outline font may
be formed on the basis of a dot font stored in, e.g., an internal
ROM of a printer, and the same processing as described above may be
executed.
In the flow chart shown in FIG. 9, when a dot pattern is
registered, generation of an outline font (step S4), registration
of the outline font (step S5), generation of a dot font (step S6),
and storage of the dot font (step S7) are executed. For example,
these steps may be executed when the resolution of the printer
engine is designated by the host computer 100, and the size of a
character printed using a currently stored dot pattern becomes
different from the designated size.
As described above, according to this embodiment, a dot pattern is
converted into an outline font, and a dot pattern corresponding to
a dot pattern having a size different from an original dot size is
formed based on the outline font, and is registered, so that a time
required for forming a character pattern can be reduced, and a
printing speed can be increased.
As described above, according to the present invention, an outline
font is formed based on a dot pattern, and a dot pattern having a
size according to a resolution of a recording unit is formed based
on the outline font, and is registered. Thus, even when a printing
resolution is changed, a high-speed printing operation can be
performed. Note that the dot pattern may be an externally input
down-load font.
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